Cocurrent packed helical coil extractor



Aug. 10, 1965 A. FERRARI COCURRENT PACKED HELIGAL COIL EXTRACTOR Filed00'0. 18, 1962 INVENTOR ANDRES FERRARI ATTORNEY United States Patent O3,199,956 COCURRENT PACKED HELICAL COIL EXTRACTR Andres Ferrari,Scarsdale, N.Y., assigner to Technicon Instruments Corporation,Chauncey, NX., a corporation of New York Filed ct. 18, 1962, Ser. No.231,540 6 Claims. (Cl. 23-267) This invention relates to appartus forthe separation of a constituent of a liquid by the use of solventextraction techniques.

One object of the invention is to provide solvent extraction apparatushaving improved means for bringing portions of the liquid solvent andthe liquid sample into intimate contact with each other for treatment ofthe sample by the solvent to extract a constituent of the sample by theaction of the solvent.

Another object is to provide solvent extraction apparatus of the typeindicated with means for separating the resulting constituent-containingsolvent from the other liquid of the resulting mixture.

A further object is generally to provide apparatus of improvedconstruction for continuously extracting and separating immiscibleliquid phases of diiierent speciic gravities, respectively, from amixture of the phases in a stream.

The above and other objects, features and advantages of the inventionwill be more fully understood from the following description of thepresently preferred embodiment of the invention considered in connectionwith the accompanying illustrative drawings.

In the drawings:

FIG. 1 is a vertical view of apparatus according to the presentinvention;

FIG. 2 is a vertical sectional view, on a larger scale, of the lower endof the apparatus of FIG. 1;

FIG. 3 is a perspective view of a part of the apparatus; and

FIG. 4 is a more-or-less diagrammatic illustration of the apparatus inconjunction with apparatus for automatically determining the quantity ofa constituent of a liquid.

Referring now to the drawings in detail, the solvent extractionapparatus comprises a liquid contact device for bringing portions of aliquid solvent and a liquid sample into intimate contact with each otherfor treatment of the sample by the solvent to extract a constituent ofthe sample by the action of the solvent. A liquid separating device 12is in fluid llow communication with the contact device 10 and isoperable to receive the resulting stream from the latter and separatethe resulting immiscible liquids of diierent specific gravities,respectively, of the stream from each other, as will be more clearlyunderstood hereinafter.

The liquid contact device 10 comprises a helical coil of tubing 14,preferably made of glass sold under the trademark Pyrex, and it is to benoted that the convolutions of the coil are relatively close to eachother so that a relatively long length of tubing is provided but whichonly occupies a relatively short length. The coil provides a liquidpassage for the ow therethrough of the liquid sample and an extractingliquid solvent wherein, during the passage of the stream through thecoil, the solvent is effective to extract a constituent of the sample.For introducing the stream containing the sample and solvent liquids,the bottom of coil 14 is provided with a tubular inlet part 16- to whichan inlet tube 18 is connected, and the upper end of the coil is providedwith a tubular outlet part 20 to which an outlet tube 22 is connected.

0 liquid phase.

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The flow passage formed by coil 14 is lled with a plurality of beads 23,preferably made of glass sold under the trademark Pyrex, which provideliquid contact surfaces that are wetted by the sample and solventliquids of the stream, whereby all portions of the solvent and sampleare brought into intimate contact with each other for the extractingaction of the solvent on the sample. Preferably the beads are in theform of hollow cylinders, as illustrated by FIG. 3, so that relativelylarge areas of contacting surfaces are provided with beads of relativelysmall dimensions. For example, each bead can be in the order of 1.0 to1.5 mm. outside diameter, 0.5 mm. inside diameter, and 0.75 to 1.01 mm.long; and with beads of the indicated size, the inside diameter of coil14 can be in the order of 3.0 mm. To retain the beads in their positionin the coil and to permit the ilow of liquid into and out of the coil,constricted openings 2d are provided in the coil and are longitudinallyspaced from each other with the beads positioned between theconstrictions. No beads are provided downstream of constriction 24 atthe outlet end of the coil so that the resulting immiscible andseparable phases have an opportunity to begin to separate before theyflow from the contact device 10.

Coil 14 can be mounted in a jacket 26, also preferably made of glasssold under the trademark Pyrex, andv temperature-controlled iiuid istransmitted through the jacket via inlet and outlet tubes 28 and 30,respectively, so that the extracting and separating operations can beconducted under controlled temperatures. The iiow of the iiuid throughthe jacket can be controlled by suitable pump. means.

The separating device 12 comprises a vertical chamber 32, preferablyformed from glass sold under the trademark Pyrex, and the chamber has anupper inlet 34 which is in liquid iiow communication with the outletpart 20 of coil 14 via tube 22, for the introduction of the liquidstream containing the immiscible and separable liquid phases into theseparating chamber. It will be understood that the solvent liquidcontaining the extracted ingredient of the sample constitutes one liquidphase of the mixture of the stream and is separable from the otherliquid phase of the stream because it is immiscible with and has adilierent specific gravity than the other liquid phase of the stream andthese physical characteristics are utilized by the separating device 12for separating the phases from each other. Chamber 32 is also providedwith an outlet opening 36 at its bottom for the resulting separatedheavier liquid phase of the stream, an-d is provided with another outletopening 38 at the upper part of the chamber for the resulting separatedlighter liquid phase of the stream.

A proportioning pump 40, preferably of the type shown and described inU.S. Patent No. 2,935,028 issued May 3, 1960, is provided forcontrolling the relative rate of iiow of the resulting separated heavierliquid phase through its outlet 36 and the heavier liquid portion of theincoming stream through inlet 34. More particularly, in the case wherethe solvent and the extracted ingredient contained therein is heavierthan the other liquid of the stream, then pump 40 is operable to pumpthe separated heavier liquid from chamber 32 through outlet opening 36at a rate of flow which is less than the rate of ilow of the heavierportion of the incoming stream through inlet 34, so that duringoperation of the apparatus, the heavier liquid phase of the streamsettles toward the bottom of chamber 32 while the lighter liquid of thestream moves toward the top of the chamber and flows out through outlet36 with a small portion of the heavier In this manner, all of theheavier phase is separated from the lighter phase and nearly all of the3 heavier phase is transmitted from the separating device, in the formof a stream, through conduit 42.

In the event that the ingredient-containing solvent is lighter than theother liquid of the stream, then pump 40 is operatedso that the rate offlow ofthe resulting separated heavier phase ot the liquid throughoutlet y36 is greater than the rate of ow of the heavier liquid portionof the stream through inlet 34. This results in the iiow of all oftheseparated heavier liquid and a small portion of the lighter liquid fromthe chamber, through outlet 36 while only the separated lighter liquidflows through outlet 38, whereby nearly all of said lighter liquid canbe transmitted,` in the form of a stream, separate from the otherliquid. As will be understood hereinafter, the separatedingredient-containing solvent stream is analyzed to determine thequantity of the ingredient present in the stream.

' Liquid contact device 10 `and separating device 12 are especiallyuseful ina continuous treatment and analysis system of the type shownand described in U.S. Patent No. 2,797,149 issued June 25, 1957, fordetermining the quantity of a substance which is present in a liquid andwhich` can be extracted from the liquidby a solvent. For example, theapparatus is especially useful in monitoring the tetraethyl lead contentof the atmosphere at or near manufactories which produce tetraethyllead. For such use, air from the atmosphere is continuously bubbledthrough a liquid, for example Water, and the resulting tetraethyl leadcontent of the .liquid is determined by transmitting the liquid, in theform of a stream, to the apparatus illustrated by FIG. 4; The liquid istransmitted to pump tube 44 of pump 40 and is transmitted, by the actionof the pump, to a fitting 46 where it joins a stream of segmentizing airor other inert and separable iluid simultaneously transmitted throughpump tube 48 and a diluent liquid, for example water, simultaneouslytransmitted through pump tube 50. It is to be understood that theseparable uid introduced through pump tube y 48 is free of anytetraethyl lead. At fitting 46, the different streams join each other toform a segmented stream comprising a series of longitudinally spacedliquid segments, separated from each other by intervening fluid segmentswhich help ymaintain the passages of the apparatus clean, as explainedin said U.S. Patent No. 2,797,149.

The constituents of each liquid segment are mixed together in theirrespective liquid segments as the segmented stream flows through thehorizontal helical mixing coil 52. From the mixing coil, the segmentedstream passes through a separating device 54 for removing the separableuid segments from the stream. More particularly, the device comprises anottake tube 56 which is connected to suction pump tube 58 via conduit60. Due to the aspirating action of the suction, the segmentizing fluidsegments are removed from the segmented stream with a minor portionof-the liquid and a consolidated liquid stream is transmitted to tting62 where it joins a stream of liquid containing a solvent and a colorproducing reagent which is transmitted through a conduit 64. In theVillustrative example of tetraethyl lead determinations, the

solvent for the tetraethyl lead is chloroform and the color producingreagent is dithizone reagent. Since the chloroform might have adverseeffects on the material of the pump tubes, it is preferably pumped totting 62 through the means of a displacement bottle 66 which containsthe solvent and color producing reagent, and a suitable liquid, forexample water, is transmitted by pump ltube GS, and introduced into thebottle for displacing an equal" quantity of the color producing reagentand solvent.

The resulting liquid stream is transmitted through conduit 18 andthrough the liquid contact device 16) whereby the solvent and reagentare brought into intimate contact with the tetraethyl lead constituentof the stream. The solvent extracts the tetraethyl lead from the liquidand, due to the action of the color producing reagent, the

liquid phase containing the` solution of chloroform and tetraethyl lead,has a color which indicates the quantity of the tetraethyl lead in thesolution. This colored liquid is separated from the remaining liquid, bythe action of the separating device 12, and is transmitted from thelatter through conduit 42 by the action of pump tube 70, to acolorimeter 72 which measures the intensity of the color to providel anindication of the quantity. of tetraethyl lead present. The results ofthe colorimetric analysis are recorded on the recorder 74.

While I have shown and described the preferred embodiment of theinvention,vit will be understood that the invention may be embodiedotherwiseY than as herein specically illustrated or described, and thatcertainchan'ges in the form and arrangement .of parts and in the specicmanner of practicing the invention may be made without departing fromthe underlying idea or principles of this invention within the scope ofthe appended claim.

What is claimed is:

1. Solvent extracting apparatus, comprisinga helical coil of tubingproviding a liquid passage and having an inlet and an outlet forthe flowof liquid through said passage,and a plurality of separate" memberspositioned in said passage in the pathlof flow of the liquid andproviding liquid impingement contact surfaces for bringing the variousportions of the liquid intointimate contact with each other, said coilof tubing having a constricted opening providing an inletfor the liquidand having another constricted opening, longitudinally spaced from saidiirst mentioned constricted opening, and providing an outlet for theliquid, said members being disposed in said passage between saidconstricted openings, and said coil of tubing having convolutionsdownstream of said constricted opening providing said outlet for theliquid, saidconvolutions having no members therein.

2. Solvent extracting apparatus, comprising a helical coil of tubingproviding a liquid passage and having an inlet and an outlet for the owof liquid through said passage, a plurality of separate ,memberspositioned in said passage in the path of ow of the liquid and providingliquid impingement contactsurfaces for bringing the various portions ofthe liquid into intimate contact with each other, said members being inthe form of hollow cylinders, and means in liquid ow communication withsaid outlet for separating one liquid phase from another liquid phaseofthe liquid from said passage dueto the im- Vmiscibility and differentspecific gravities of thephases,

said separating means'comprising a vertical chamber having an inletopening inY liquid ow communication with said outlet through which theliquid from said passage is introduced into said chamber, an outletopening below said inlet opening for ow from the chamber of theresulting separated heavier liquid phase, another outlet opening abovesaid first mentioned outlet opening for the ow from the chamber of theresulting separated lighter liquid phase, .and pump means in liquid Howcommunication with said inlet opening and said irst mentioned outletopening of said chamber for controlling the relative rates of flow ofthe separated heavier liquid through said irst mentioned outlet and theheavier liquid portion of the incoming liquid through `said inletopening.

Y3. Solvent extracting apparatus, comprising a helical coil of tubingproviding ,a liquid passage and having an inlet and an outlet for theilow of liquid through said passage, a plurality of'separate memberspositioned in said passage in the path of flow of the liquid andVproviding liquid impingement contact surfaces for bringing the variousportions of the liquid into intimate contact with each other, said coilof tubing having constricted openings longitudinally spaced from eachother for retaining said members in said passage while permitting theflow of the liquid through said passage, a jacket-enclosing said coiland having an inlet and an outlet for the ow of temperature controlleduid through. the jacket and around said coil of tubing, said membersbeing in the form of hollow cylinders, and means in liquid flowcommunication with said outlet for separating one liquid phase fromanother liquid phase of the liquid from said passage due to theimmiscibility and different specific gravities of the phases, saidseparating means comprising a vertical chamber having an inlet openingin liquid How communication with said outlet through which the liquidfrom said passage is introduced into said chamber, an outlet openingbelow said inlet opening for flow from the chamber of the resultingseparated heavier liquid phase, another outlet opening above said firstmentioned outlet opening for the ow from the chamber of the resultingseparated lighter liquid phase, and pump means in liquid owcommunication with said inlet opening and said first mentioned outletopening of said chamber for controlling the relative rates of flow ofthe separated heavier liquid through said iirst mentioned outlet and theheavier liquid portion of the incoming liquid through said inletopening.

4. Immiscible liquids interaction apparatus comprising:

a helical coil of a plurality of turns of tubing providing a liquidpassageway and having an inlet and an outlet for the flow of liquidsthrough said passageway;

a plurality of individual tubular members disposed in the path of flowof the liquids and providing impingement contact surfaces for bringingthe various constitutents of the liquids into intimate contact with eachother;

a jacket enclosing said coil and having an inlet and an outlet for theow of temperature controlled iluid through said jacket and around saidcoil;

said coil having a constriction in one of its turns, for dividing saidcoil into an upstream portion and a downstream portion;

said members being disposed solely in said passageway in said upstreamportion, permitting free ow of liquids through said passageway in saiddownstream portion.

5. Immiscible liquids interaction apparatus comprising:

a helical coil of a plurality of turns of tubing providing a liquidpassageway and having an inlet and an outlet;

said coil having a constriction in one of its turns, for dividing saidcoil into an upstream portion and a downstream portion;

a plurality of individual tubular members randomly disposed solely insaid passageway in said upstream portion in the path of flow of theliquids and providing impingement contact surfaces for bringing thevarious constituents of the liquids into intimate contact with eachother, while permitting free flow of liquids through said passageway insaid downstream portion;

a jacket enclosing said coil and having an inlet and an outlet for theow of temperature controlled i'luid through said jacket and around bothsaid upstream and said downstream portions of said coil; and

source means of a plurality of immiscible liquids coupled to said inletof said coil for passing the liquids into said coil under pressure.

6. Immiscible liquids interaction apparatus comprising:

a helical coil of a plurality of turns of tubing providing a liquidpassageway and having an inlet and an outlet;

said coil having a constriction in one of its turns, for dividing saidcoil into an upstream portion and down stream portion;

a plurality of individual tubular members randomly disposed solely insaid passageway in said upstream portion in the path of ow of theliquids and providing impingement contact surfaces for bringing thevarious constituents of the liquids into intimate contact with eachother, while permitting the free flow of liquids through said passagewayin said downstream portion;

a jacket enclosing said coil and having an inlet and an outlet for theflow of temperature controlled luid through said jacket and around bothsaid upstream and said downstream portions of said coil;

separating means coupled to said oulet of said coil for separating oneimmiscible liquid from another including a vertical chamber having aninlet coupled to said outlet of said coil, a first outlet below saidinlet for the flow from said chamber of the separated denser liquid, asecond outlet above said irst outlet and below said inlet for the owfrom said chamber of the separated less dense liquid; and

pump means coupled to said inlet of said coil for supplying thereto at agiven rate the two immiscible liquids, and to said rst and secondoutlets of said chamber for removing therefrom at given rates the twoseparated immiscible liquids.

References Cited by the Examiner UNITED STATES PATENTS 426,586 4/ 90Gillet 261-94 2,852,349 9/58 Hicks 23-270.3 3,109,870 11/ 63 Kuhn23-270.5

FOREIGN PATENTS 642,068 8/50 Great Britain.

OTHER REFERENCES Bulletin TP54, Tower Packing, 1957, U.S. Stoneware Co.,Akron 9, Ohio.

NORMAN YUDKOFF, Primary Examiner.

1. SOLVENT EXTRACTING APPARATUS, COMPRISING A HELICAL COIL OF TUBINGPROVIDING A LIQUID PASSAGE AND HAVING AN INLET AND AN OUTLET FOR THEFLOW OF LIQUID THROUGH SAID PASSAGE, AND A PLURALITY OF SEPARATE MEMBERSPOSITIONED IN SAID PASSAGE IN THE PATH OF FLOW OF THE LIQUID ANDPROVIDING LIQUID IMPINGEMENT CONTACT SURFACES FOR BRINGING THE VARIOUSPORTIONS OF THE LIQUID INTO INTIMATE CONTACT WITH EACH OTHER, SAID COILOF TUBING HAVING A CONSTRICTED OPENING PROVIDING AN INLET FOR THE LIQUIDAND HAVING ANOTHER CONSTRICTED OPENING, LONGITUDINALLY SPACED FROM SAIDFIRST MENTIONED CONSTRICTED OPENING, AND PROVIDING AN OUTLET FOR THELIQUID, SAID MEMBERS BEING DISPOSED IN SAID PASSAGE BETWEEN SAIDCONSTRICTED OPENINGS, AND SAID COIL OF TUBING HAVING CONVOLUTIONSDOWNSTREAM OF SAID CONSTRICTED OPENING PROVIDING SAID OUTLET FOR THELIQUID, SAID CONVOLUTIONS HAVING NO MEMBERS THEREIN.